Not hollow, they just don't produce light on the inside. What is inside is the "wax" vapor that is used as fuel. Only when that fuel contacts the oxygen in the atmosphere can it burn and thus produce light.
Not hollow, they just don't produce light on the inside. What is inside is the "wax" vapor that is used as fuel. Only when that fuel contacts the oxygen in the atmosphere can it burn and thus produce light.
Not hollow, they just don't produce light on the inside. What is inside is the "wax" vapor that is used as fuel. Only when that fuel contacts the oxygen in the atmosphere can it burn and thus produce light.